Why do you seldom see any effects from the strong interactions that can occur between charges?

Answer 1

Because most of the time, the objects concerned are electrically neutral or bear only a small net electric charge, making other interactions such as gravity the dominant interaction. For example, an electrically charged ball will fall to the ground most of the time, even if placed beneath another object bearing the opposite charge, because the ball would have to be very light and very stronly charged in order to make the electrical Coulomb interaction strong enogh to become comparable to the gravitational force exerted on the ball by the earth's mass. In some cases however, such as a single electron flying through the electric field of a capacitor, the charge of the particle with respect to its mass is so big that gravity is neglectable compared to the Coulomb interaction.